The Proper Exposure of Raw Images
In this blog I am going to avoid the many intricate details of using photo software. There are so many Photoshop / Lightroom gurus out there who seemingly spend every waking hour studying these programs that any effort I made would be superfluous. However, there is a need, I believe, to comment on some general guiding principles which are lesser known.
One area I often see where misconceptions arise is the exposure of raw images in-camera. In this regard, the golden rule was laid out long ago by the well-known photoshop guru – the late Bruce Fraser. In one short read Bruce set forth the definitive principles and technical theory behind raw file exposure. I read his white paper years ago, and thankfully Adobe has made it still available as a pdf here. Rather than go into it myself, please download and read the pdf, which is a masterpiece of brevity and was a trailblazing revelation at the time on the mysteries of the raw file. I often hear even professionals say they under-expose raw files “like film” to protect the highlights. So read Bruce Fraser, become enlightened and “expose to the right” in your histogram as I did in this “froggy” shot. Half the tonal levels your camera can record are in the brightest stop!
A related area of confusion for some concerns “Picture Styles” as they are called in general. These are settings you make in-camera and can be somewhat misunderstood. Because photographers in general know that raw files are “developed” in software settings/sliders for output to some other final file format (TIFF, PSD, JPEG) it is understood that the raw file remains intact and untouched by these software settings or as Canon calls them in DPP 4 “recipes.” However, because sliders are set to zero when raw files come into processing software, one could be forgiven for thinking nothing has been done to the raw files as yet. However, we are looking at a jpeg representation of the raw file at this stage, and even before in camera, as Bruce Fraser explains. The crucial point is that the “Picture Style” that was set in camera is a manufacturer specific set of patented instructions or “recipes” if you will, which are ALREADY baked into the jpeg representation of the file. These include the colour science I referred to in my previous blog, contrast, noise reduction, lens correction etc. So the various “Picture Styles” (Landscape, Portrait, Neutral etc.) have already set up a definite look before you even start post-processing. This can be helpful or a hindrance depending on what your final processing goal is. For instance “Landscape” will have more contrast and sharpening and strongly saturated greens and blues, but “Portrait” softens contrast / sharpening and ramps up reds for more pleasing skin tones.
Since I wrote this blog, my link to Bruce Fraser’s pdf no longer works. My apologies – perhaps you can find it at Adobe in another location.